RT Journal Article SR Electronic T1 The prevalence of the c-kit exon 10 variant, M541L, in aggressive fibromatosis does not differ from the general population JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 1021 OP 1024 DO 10.1136/jcp.2011.090498 VO 64 IS 11 A1 Florian Grabellus A1 Karl Worm A1 Sien-Yi Sheu A1 Winfried Siffert A1 Kurt W Schmid A1 Hagen S Bachmann YR 2011 UL http://jcp.bmj.com/content/64/11/1021.abstract AB Background The frequency of the c-kit exon 10 variant, M541L, (c.1621 A>C) in aggressive fibromatosis (AF) was recently determined to be 2.5-fold higher than in healthy controls. It was thus hypothesised that M541L could be associated with the development of AF.Methods 42 cases of sporadic AF were investigated for c-kit exon 10 alterations, by traditional sequencing. Subsequently, the AF cases and 126 healthy volunteers were screened for the M541L by pyrosequencing.Results Genotype frequency of M541L in AF was 16.7% (allele frequencies: A, 0.92 and C, 0.08), which did not differ from the control group. Moreover the M541L variant was found to be not tumour specific.Conclusions The result classifies the M541L variant of c-kit exon 10 as a single nucleotide polymorphism. Because its prevalence does not differ between the AF and general populations, an association with AF tumourigenesis is unlikely.